sp_helpconstraint (Transact-SQL)

Returns a list of all constraint types, their user-defined or system-supplied name, the columns on which they have been defined, and the expression that defines the constraint (for DEFAULT and CHECK constraints only).

sp_helpconstraint displays a descending indexed column if it participated in primary keys. The descending indexed column will be listed in the result set with a minus sign (-) following its name. The default, an ascending indexed column, will be listed by its name alone.